1. Field of the Invention
The present invention relates to a built-up type box-shaped steel column for filling concrete therein and a method for manufacturing the same, and more particularly, to a built-up type box-shaped steel column for filling concrete therein, that can be formed easily and economically in a built-up scheme by using ┐-shapes and steel plates, and a method for manufacturing the same that includes bonding a steel plate at the inner surface of ┐-shapes during a process of making a built-up type box-shaped steel column, thereby having good resistance against a lateral pressure of concrete filled in the steel column and preventing a bonded portion from being exposed to the outside thus to provide a better outer appearance.
2. Background of the Related Art
Generally, a CFT (Concrete Filled Tube) structure is formed by filling concrete at the inside of tubular steel columns, thereby having good advantages in the stiffness, yield strength, the capability of elongation, fire resistance, and construction thereof.
Typically, most of the tubular steel columns that are employed in the CFT structure are formed integrally or are finished with the steel plate assembled therewith. Such the tubular steel columns are customized and manufactured in large-sized factories where specific manufacturing equipment is prepared, which causes the production costs to be inevitably high. This also creates another problem in that the applicability of the CFT structure is somewhat restricted. Although the CFT structure has actually the advantages of the structural stability and construction capability thereof, it is generally adopted only for the construction of the low floors of high large-scaled buildings.